Final answer:
The strongest counter-argument against Cory's argument is that the shared traits of aardvarks and anteaters are due to convergent evolution, occurring independently rather than inherited from a common ancestor.
Step-by-step explanation:
The claim that would provide the strongest counter-argument against Cory's argument is: The tongues and diet of aardvarks and anteaters are an example of convergent evolution.
Convergent evolution occurs when different species develop similar traits or adaptations independently, usually because they live in similar environments or have similar ecological roles. This does not necessarily mean that they share a recent common ancestor with those traits. The similar tongue adaptations in aardvarks and anteaters could have evolved separately as a result of both species adapting to a similar diet of ants and termites, not because they inherited this feature from a common ancestor.
Convergent evolution is observed in many other species, such as the development of flight in both insects and birds, despite their very different ancestries. Similarly, both whales and fish have streamlined bodies suitable for swimming, but not because of recent common ancestry. These independent evolutionary paths to similar features underscore the role of natural selection in shaping the adaptations of organisms to their environments.